1. Field of the Invention
The invention relates in general to a flat panel display and a pixel driving method applied thereto, and more particularly to a flat panel display and a pixel multiplexing driving method applied thereto.
2. Description of the Related Art
In a conventional flat panel display, each pixel is connected to a data line and a scan line separately and is provided a corresponding data voltage and an corresponding scan voltage by a driving circuit. Because of the requirements of current market, the size of the flat panel display is getting larger and the resolution is getting higher, so that the cost of the driving circuit and the cost of the flat panel display are getting more. Therefore, the flat panel display with pixel multiplexing structure appears in order to reduce the cost of the display and increase the competitiveness in the market.
Referring to FIG. 1, a pixel multiplexing structure in a conventional flat panel display is shown. Also referring to FIG. 2, a waveform of the signals provided to the scan voltage and the data voltage according to the flat panel display in FIG. 1 is shown. The pixel array 100 adopts the pixel multiplexing method where one data line respectively provides two data voltages to the two pixels adjacent to the data line. The following takes the adjacent two pixels A and B in the Nth pixel row Ln as an example where the adjacent two pixels are connected to the data line Dm and the scan line Gn. First, in the time period from t0 to t1, the scan line Gn provides a scan voltage Vn to the Nth pixel row to conduct the corresponding thin film transistor (TFT) M2. Also, the next scan line Gn+1 provides a scan voltage Vn+1 via the conducted TFT M2 to the corresponding TFT M1 to conduct the TFT M1, thus the TFT M1 outputs a data voltage D1 of the data line Dm to the corresponding pixel A. Besides, the scan voltage Vn outputted by the scan line Gn conducts the corresponding TFT M3, thus the TFT M3 outputs the data voltage D1 of the data line Dm to the corresponding pixel B. Wherein the scan voltage Vn is substantially equal to the scan voltage Vn+1.
However, according to the characteristic of TFT, when the TFT M2 is conducted, the gate voltage of the TFT M1 outputted from the TFT M2 is not equal to the scan voltage Vn+1 provided by the scan line Gn+1. Instead, the gate voltage of TFT M1 is lower than the scan voltage Vn+1 by a threshold voltage. That is, the gate voltage of the TFT M1 is 20V−5V=15V. Moreover, the gate voltage of the TFT M3 is equal to the scan voltage Vn of the scan line Gn (=20V). In other words, when the pixels A and B receive the data voltage D1 in the time period from t0 to t1, the gate voltage of the TFT M1 (=15V) is substantially lower than the gate voltage of the TFT M3 (=20V), such that the charging capability of the pixel A is worse than that of the pixel B. Also, the unequal charging capability between pixel A and B may cause the phenomenon of flickering on the flat panel display.